This thread is a bit old; sorry I didn't see it sooner. In part, I think your difficulty lies in the fact that scholars working in different (geographic) areas often gravitate toward differing academic interests. "Central Places" is really a concept that has gained the most traction in southern Scandinavia and to a lesser extent around the early medieval North Sea. These tend to be wealthy aristocratic sites, but without obvious economic or military function. Contemporary sites in neighboring regions often tend to have more of an economic or military dimension, so the notion of "central place" is often supplanted by a more useful model. Insofar as I know (and this steps outside my area of general competence), the correspondent sites in Central and Eastern Europe (as well as the North Mediterranean) tend to be more frequently described as hill forts. Chris Wickham's Framing the Early Middle Ages does a stellar job of talking about what makes these regions different, and what makes the scholarship on them different as well, although his weighty tome is best dealt with by reading small focused chunks one at a time. I can't recall what its maps look like, but it might be a good first stop.

With regard to the specifics of the Baltic region, I'd point you to a really interesting article recently published. The author has posted a pdf version on his academia homepage.

• Volkmann, Armin. “Climate Change, Environment and Migration: A GIS-Based Study of the Roman Iron Age to the Early Middle Ages in the River Oder Region.” Post-Classical Archaeologies 5 (2015): 7–32.

For the areas surrounding the North Sea, central places remains a useful model during the Migration Period, although later on these seem to be supplanted by sites that scholars are more likely to describe as minsters (religious sites), emporia (trading settlements; singular form, emporium), or burhs (military sites). Two sites that come immediately to mind are Lyminge in southern England and Yeavering in the north; the first site that comes to mind for the Continent is Metz, and a quick search turned up some comparisons with Trier. Above all, I'd point you to:

• Helena Hamerow, Early Medieval Settlements: The Archaeology of Rural Communities in Northwest Europe 400-900 (New York: Oxford University Press, 2002).

For two other general recommendations, I've really enjoyed Lotte Hedeager's work on Denmark during the Migration Period, although care should be taken when reading her text; she's making arguments, not representing the consensus of the field. I also think that Pat Geary's introduction to the Migration Period remains the best one out there, in terms of a quick and lively read, although Guy Halsall (Barbarian Migrations), Robin Fleming (Britain After Rome), et al., have more recent studies. With regard to maps, Halsall's Barbarian Migrations might actually be a best first step, although it does little to address your question about Central Places.

• Lotte Hedeager, Iron Age Myth and Materiality: An Archaeology of Scandinavia, AD 400-1000 (London: Routledge, 2011).

• Patrick J. Geary, Before France and Germany: The Creation and Transformation of the Merovingian World (Oxford: Oxford University Press, 1988).